BAGHOUZ, Syria (AP) — U.S.-backed Syrian forces fighting the Islamic State group announced Tuesday they have taken control over an encampment in an eastern Syrian village where IS militants have been besieged for months, refusing to surrender.

The milestone, though significant, was not the final defeat of IS in the village of Baghouz, the last sliver of territory in Syria held by the extremists.

Mustafa Bali, the spokesman for the Kurdish-led force known as the Syrian Democratic Forces, said that however, clashes were continuing elsewhere in the village as IS militants continue to fight back.

“This is not a victory announcement, but a significant progress in the fight,” Bali said in a Twitter post. He said hundreds of wounded and sick militants were captured and have been evacuated to nearby military hospitals for treatment.

The area held by IS in Baghouz is the last pocket of territory in Syria controlled by the extremist group, which once held a vast area of Syria and Iraq, calling it an Islamic “caliphate.” The capture of Baghouz would mark the end of the devastating four-year campaign to end IS’s hold on any kind of territory, although it maintains scattered presence and sleeper cells in both countries.

The battle to capture Baghouz — including the encampment, a collection of tents covering foxholes and underground tunnels — has dragged on for weeks amid an unexpected exodus of civilians from the area.

The sheer number of people who have emerged, nearly 30,000 since early January according to Kurdish officials, has taken the Kurdish-led Syrian Democratic Forces by surprise. Most have been women and children whose existence in a labyrinth of underground caves and tunnels was unknown to the U.S.-backed fighters.

In the last two weeks, many IS militants appeared to be among those evacuating. But SDF commanders have stopped speculating when the battle may finally be over. Commanders say they don’t know how many more may still be left, hiding in tunnels beneath the war-scarred village.

The militants have been putting up a desperate fight against SDF advances.

Another SDF commander, who goes by his nom de guerre Zana, said clashes were ongoing in Baghouz, adding that the militants are still holding some families as human shields.